Problem: What is the surface area of this box? Drag on the box to rotate it. $3$ $7$
Explanation: To find the surface area, find the areas of each of the faces, and add all the areas up. To see this better, let's try unwrapping the box: We can group the faces together based on size and color: $3$ $5$ $5$ $7$ $7$ $3$ We can calculate the area of each of the pieces now: $ 2 \left(5 \times 3\right) + 2 \left(7 \times 5\right) + 2 \left(3 \times 7\right) $ $ = 30 + 70 + 42$ $ = 142 $ Thus, the total surface area of the box is $142$.